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#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>

typedef struct RelFileNode
{
  unsigned int spc;
  unsigned int db;
  unsigned int rel;
} RelFileNode;

typedef struct Buffer
{
  RelFileNode rnode;
} Buffer;

//#define NBUFFERS ((int)((128.0 * 1024 * 1024 * 1024) / (8.0 * 1024)))
#define NBUFFERS ((int)((32.0 * 1024 * 1024 * 1024) / (8.0 * 1024)))
int main(void) {
  int i;
  RelFileNode t = {1,2,3};
  Buffer *bufs = (Buffer *) malloc(sizeof(Buffer) * NBUFFERS);
  struct timeval st, ed;
  int matches = 0, unmatches = 0;
  Buffer *b;

  for (i = 0 ; i < NBUFFERS ; i++) {
	bufs[i].rnode.spc = random() * 100;
	bufs[i].rnode.db = random() * 100;
	bufs[i].rnode.rel = random() * 10000;
  }

  /* start measuring */
  gettimeofday(&st, NULL);

  b = bufs;
  for (i = 0 ; i < NBUFFERS ; i++) {
	if (b->rnode.spc == t.spc && b->rnode.db == t.db && b->rnode.rel == t.rel)
	  matches++;
	else
	  unmatches++;

	b++;
  }
  gettimeofday(&ed, NULL);

  printf("%lf ms for %d loops, matches %d, unmatches %d\n",
		 (double)((ed.tv_sec - st.tv_sec) * 1000.0 +
				  (ed.tv_usec - st.tv_usec) / 1000.0),
		 i, matches, unmatches);

  return 0;
}